I have 2 denso heated o2s, and a acdelco heated o2.

I've tried them all

once it goes into closed loop the BLM stays at 128, but INT starts going down and it stalls. keeps stalling a few seconds after I start it up again

when I put in my 1wire o2 BLM&INT stay at 128 when its in closed loop

also I notice the o2 cross counts go up fast on the non-heated one once its warmed up.

with the heated ones it either goes up slow as shit, or not at all

Are your o2s new.I have had good results from the A/C delco AFS74 and AFS75.Do you have both grounds from the o2 ran to the same spot...If so move one to another location.Do yourself a favor and buy a wideband.You can get one from RPM outlet for 279.99 plus shipping and it's the same as the AEM kit that cost over 400 plus dollars.It has two analog outputs and one will do a 0-1volt reference to keep your computer happy.I run open loop ALL THE TIME :icon_eek: (keeping the wideband happy)so I don't need that function but if you wont closed loop you got it.If you have slow or no cross counts the o2 is USUALLY bad..Later..Adam

Quote from: flybynite on December 10, 2006, 01:07:19 PM
Are your o2s new.I have had good results from the A/C delco AFS74 and AFS75.Do you have both grounds from the o2 ran to the same spot...If so move one to another location.Do yourself a favor and buy a wideband.You can get one from RPM outlet for 279.99 plus shipping and it's the same as the AEM kit that cost over 400 plus dollars.It has two analog outputs and one will do a 0-1volt reference to keep your computer happy.I run open loop ALL THE TIME :icon_eek: (keeping the wideband happy)so I don't need that function but if you wont closed loop you got it.If you have slow or no cross counts the o2 is USUALLY bad..Later..Adam

I do have the heater ground and sensor ground running to the same spot. I will try moving one. thanks!

Same...

had good luck with AC delco's but not Bosch O2's

I seperated the grounds.

now the o2 cross counts were going up quick right away, but then after about 3 minutes they stopped moving

it didnt go into closed loop either, and should have by that long?

Run the non heater O2s ground stright to the ECM box's chassis. You might have a badly ground engine or ground wires on the car frame to battery.

maybe the ground is too long?  shouldn't ever be longer than 18 inches.

Quote from: GangstGP on December 12, 2006, 02:28:25 PM
maybe the ground is too long?  shouldn't ever be longer than 18 inches.

Do what? Which ground should not be longer than 18"? Where are you getting this measurment from? What gauge wire is limited to 18" and from what point to what point?

its a general "rule of thumb" for all  wireing on all 12 volt shit. it can be longer but 1. no need 2. more resistence.

grounds need to be improved, but making them longer does not improve them.

Quote from: GangstGP on December 14, 2006, 03:18:13 PM
its a general "rule of thumb" for all  wiring on all 12 volt shit. it can be longer but 1. no need 2. more Resistance.

grounds need to be improved, but making them longer does not improve them.

You may want to pay closer attention to the under hood wiring and how fuel injectors are wired and fired, along with how coils are wired and fired, or how wiring from a switch, to a relay, then to a motor is wired on most 12vDC systems.

You also need to consider basic Ohm's Law for what is required to properly wire and feed any loading device.

Lastly...you are telling me that in a 12vDC system with say 10amp load...if I have a piece of 10 gauge wire 18" long it will have less resistance and flow more power than a 10 gauge wire 4' (feet) long?

THIS IS YOUR FINAL WARNING FOR POSTING YOUR OFF THE CUFF BS INFO AS FACTUAL!

Do our grounds need to be improved? When the connections are dirty or internally corroded. We have heavy gauge wire in place that seems to work just fine for most. I can touch any portion of my motor with one lead on the ohm meter and any area that is a clean ground and see 0-0.5 ohms of resistance. Seems to work just fine for thousands.

There is only one concern with long wire O2 sensors..and thats Radio Interferance from either coils, or actual radio signals, but the ecm should have a filter built in to filter it out from the O2 wire.

Yes I agree that an 02 sensor's wiring should be shielded and well grounded (remotely), but Gangstgp has stepped in with his two cents about something he knows nothing about yet again and stated it as fact.

Back on topic...
Our cars are are not the best thing to base an ideal setup on anyway...but it works just fine. One wire using the body of the 02 as a ground. Same wire travels clear across the engine bay and to the ECM on the other side of the car. When doing datalogging or sets, I have never seen noise in the 02 signal except when it is close to failing.

Unless you are running another 02 like Adam spoke of which runs W/B and Narrow signal there is no sense to "upgrading" what we have on there. It takes 30-45 seconds for our 02 to fire off. If you do not let your car sit for at least 45 seconds on a cold morning...your 02 sensor is the LEAST of your worries!

once again, I have been here WAY before you got this gig. It is a FACT that that is a rule of thumb for car electronics, and I have proof of this in a instruction manual from one of the top car audio manufacturers in the world for wiring their amplifiers. now I have never seen a ground in a car much longer than 18 inches stock so let me know if you can find one. maybe the block-to-battery but thats much thicker than the rest.


You want to argue the fact that longer wires need to be thicker to carry the same signal?

ok guys I figured out the problem and it wasnt the ground itself, but I had the wires mixed up

on heated o2's there is 2black wires (or which ever wires are 2 of the same color) and one of those goes to 12v, the other ground. you can even switch them around

before I had both black wires going to ground, the purple to ecm and the white wire to switched 12v

very confusing how they made the wires but oh well I know now

Usually with sensors you aren't drawing very much current so the main thing is avoiding noise and making a clean connection. Length of wire is much less of a concern. Whereas with an amp or anything that needs real juice, length of wire really plays a part. Voltage drop is dependant upon current. A clean connection is always a must. I'm not a mechanic, but I know how electricity operates.